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Scientists Regrow Chicken Wing
An anonymous reader writes "Unlike salamanders and lizards, most animals have lost the ability to replace missing limbs. But a research team in San Diego has been able to regenerate a wing in a chick embryo — a species not known to be able to regrow limbs — suggesting the potential for such regeneration exists innately in all vertebrates, including humans." From the article: "Manipulating Wnt signaling in humans is, of course, not possible at this point, Belmonte says, but hopes that these findings may eventually offer insights into current research examining the ability of stem cells to build new human body tissues and parts. For example, he said Wnt signaling may push mature cells go back in time and 'dedifferentiate' into stem-like cells, in order to be able to then differentiate once more, producing all of the different tissues needed to build a limb."
New KFC Neverending bucket of chicken!
For when just one heart bypass won't do.
*mmmmm neverending chicken wings*
Maybe the ability to have consequences for being stupid enough to get your leg taken off is a net positive for a species, though it's an obvious negative for an individual? I have no idea. That would be like a meta-evolution there, and kind of anthropomorphises the theory.
It's possible that they never had the ability as environmental influences didn't lead to regeneration being a evolutionary edge.
:)
Lizards on the other hand probably had a different evolutionary environment where regeneration lead to an increase in survival.
Then again, I'm a business student so chances are I'm wrong
From TFA:
Turn it down to 0 and you eventually die of old age. Turn it up to 11 and you die of cancer. If the human equivalent can be found we may have a whole class of very old people who debate ways of achieving the right balance.
If something like this is under trial in 20 years or so I will definitely be giving it a go.
http://michaelsmith.id.au
Lizards could have picked up the ability after birds and mammals split off from reptiles. IANA paleontologist, of course, so I have no idea when lizards picked up the ability.
Alternatively, it could simply not have been useful enough for the early mammals and birds. Selection pressure only applies to things that increase your ability to reproduce. (Survive to reproductive age, find a mate, and produce viable offspring.) And if, say, flight or fur proved to be more advantageous than regenerating a tail, flight and fur would win out.
Remember, evolution isn't a ladder, it's a tree. Or maybe a branching vine would be more appropriate an analogy. There's no absolute "better" or "worse" -- just better or worse for a particular ecological niche.
Considering that even God apparently can't heal amputees.
Ellen Heber-Katz, a professor at the Wistar Institute in Philadelphia, was working with mice that had been genetically engineered to develop lupus when she noticed that some of their ears looked weird. She had punched holes in them so she could separate her control from her treatment groups in an experiment. But the holes quickly grew shut without a trace -- not even a hint of a scar.
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The missing ear holes confused her research at the time, but the phenomenon launched a whole new career for Katz.
She and her colleagues wanted to find out if other parts of these mice, known as the MRL strain, would also regenerate. So they performed some tests: They snipped off the tip of a tail, severed a spinal cord, injured the optic nerve and damaged various internal organs.
All of the injuries healed, even the severed spinal cord. The results caused Heber-Katz to shift her research from autoimmune disease to regenerative medicine.
Now, thanks to Darpa's call for grant applications in regeneration, scientists all over the country from various disciplines are working together on the MRL mouse...
More at http://www.wired.com/news/technology/medtech/0,71
john wayne bobbitt lets out a sigh of relief.........
"be on your toes... you b*tch ass hoes... when I mindflay foes cos' i spec'd to pure shadow."
Now we need to genetically modify chickens with genes from a variety of peppers, onions, garlic, herbs .. etc so that they have sweat glands that produce barbecue sauce.
Cue the "grow bigger, extra pen1s NOW!" junk emails in about 5, 4, 2...
In coding, each feature has a cost associated with it. Nothing is free. A feature will result in the combination of one or more of the following: more design/coding time, higher memory use, more CPU use, a higher chance of bugs, etc.
Evolution is the same.
For some creatures, the advantages are outweighed by the disadvantages.
For other creatures, the disadvantages are outweighed by the advantages. For many creatures, perhaps regenerating the limb isn't that useful -- the biology of the animal might mean that the loss of a limb is general fatal due to blood loss or infection (assuming the animal survives the accident/attack, which may be unlikely).
In addition, just because a feature may be a net advantage for a creature doesn't mean that it will magically appear. Genetic mutation is a crapshoot. Regeneration might have been perfected after the split from the decendents of other animals. Or perhaps the common ancestor of (say) salamanders and mammals was capable of generation, but after the split happened, regeneration had too high of a cost for the line that lead to mammals, and the genetic code was lost or adapted for some feature that was more useful.
I hope that explanation helps.
"...you see, you see, it really is just a flesh wound!"
Dear 1800-MYPEEPEE,
I would like to complain. I purchased your product and followed the instructions exactly.
Something is growing back, but it appears to be taking the shape of a chicken wing...
Get the beer kegs ready - endless chicken wings await. Once they learn how to regrow hot sauce western civilization will be complete.
A Multiplayer Strategy Game for Mac OS X, Windows, and Linux
what did it taste like?
:(){
The explanation that I am familiar with (and if there are any evolutionary biologists present, feel free to correct me) is that regeneration is too time consuming for a warm blooded animal.
With a reptile or amphibian, the wounded individual can afford to lose the weeks or more of downtime while their wounds or missing limbs regenerate. With a mammal or bird, the constant need for food to fuel a warm blooded metabolism wouldn't give a wounded individual time to heal in the same fashion; instead of regeneration, we scar instead. To use an technological metaphor, mammals slap a patch on the wound for faster recovery, while reptiles take the time to do a thorough repair job.
In any case, in the wild complete loss of limb would almost always be fatal for a mammal (barring infection or blood loss, you might live long enough to starve to death), so faster, incomplete healing via scarring is going to be good enough for most of the injuries we'd have a chance to recover from. We trade the ability to recover fully for the ability to recover quickly.
Today of course we no longer die as easily from our wounds, or from the inability to fend for ourselves after being crippled, so we have a vested interest in reworking this process. If we could induce regeneration in amputees for example, we could put them in a hospital for however long it takes to grow back and regain the use of their limbs - something we never could have done in our evolutionary history.
Erotic is when you use a feather. Exotic is when you use the whole chicken.
I hope science figures this stuff out soon, I would like to get my foreskin back.
It isn't a question of it being an energy drain, it's a question of how long the injury affects you. If it's a choice between getting hurt then regenerating over a period of weeks (during which the wound will affect your ability to function), and getting hurt then healing with scarring over a period of days (thus shortening the vulnerable period), then the latter makes more sense for us. The former makes more sense for reptiles, who can go for weeks to months without food, which we obviously cannot. Remember that doing the job right takes time, whereas a quick and dirty fix does not.
Of course, in reality it probably isn't a clear cut either/or scenario, but more likely a spectrum ranging from one extreme to the other (faster healing versus complete healing). In that sense, we do regenerate (our wounds heal, don't they?), we just don't regrow lost limbs, or heal without permanent marks.
Erotic is when you use a feather. Exotic is when you use the whole chicken.
most of our genetic code doesn't actually *do* anything as far as we can tell
Emphasis mine. Just because we don't know what "junk DNA" is for doesn't mean it's not useful. When we manage to build a cell without junk DNA and have it work perfectly, we'll be able to prove that there's no use to it. It might even just be there for padding, like the polystyrene pellets in a box. Just because you throw them out right away doesn't mean there's no use to them - they protect what you really needed to protect inside the box. The more junk you have, the more likely that mutation is going to happen in a "junky" area rather than the genes you actually need...
Seven puppies were harmed during the making of this post.
RTF: The same process that encourages regeneration also causes cancer. Cancer is such a huge problem that it counteracts the obvious advantages of long life and limb regeneration.
Once we figure out better ways to control cancer outbreaks in our cells, amazing opportunities to manipulate our bodies will become available to us.
Understanding and controlling cancer is the key to everything.
Why are you letting these clowns ruin our country?
Just because we don't know what "junk DNA" is for doesn't mean it's not useful.
Researchers are starting to point this out.
A recent example: The sequencing of the DNA of the domestic chicken found a 20,000-base-pair "non-coding" (i.e., "junk") sequence that is very nearly identical with a sequence in human DNA. For such a long sequence to be preserved is highly unlikely unless it has a strong adaptive advantage. We don't have any idea what it does, but the only reasonable conclusion is that it's very important to both chickens and humans. That's the only way it could have been preserved for the roughly 180 million years since our last common ancestor.
Either that, or it's a retrovirus that infects both species and recently invaded both genomes. Possible, but a lot less likely.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.